lib/model: Remove path from enc errors and report only once (#7610)

lib/model/model.go

@@ -15,6 +15,7 @@ import (
 	"fmt"
 	"io"
 	"net"
+	"os"
 	"path/filepath"
 	"reflect"
 	"runtime"
@@ -192,6 +193,8 @@ var (
 	errEncryptionNotEncryptedRemote    = errors.New("folder is configured to be encrypted but not announced thus")
 	errEncryptionNotEncryptedUntrusted = errors.New("device is untrusted, but configured to receive not encrypted data")
 	errEncryptionPassword              = errors.New("different encryption passwords used")
+	errEncryptionTokenRead             = errors.New("failed to read encryption token")
+	errEncryptionTokenWrite            = errors.New("failed to write encryption token")
 	errEncryptionNeedToken             = errors.New("require password token for receive-encrypted token")
 	errMissingRemoteInClusterConfig    = errors.New("remote device missing in cluster config")
 	errMissingLocalInClusterConfig     = errors.New("local device missing in cluster config")
@@ -1381,9 +1384,12 @@ func (m *model) ccHandleFolders(folders []protocol.Folder, deviceCfg config.Devi
 			if sameError {
 				l.Debugln(msg)
 			} else {
+				if rerr, ok := err.(*redactedError); ok {
+					err = rerr.redacted
+				}
+				m.evLogger.Log(events.Failure, err.Error())
 				l.Warnln(msg)
 			}
-			m.evLogger.Log(events.Failure, err.Error())
 			return tempIndexFolders, paused, err
 		}
 		if devErrs, ok := m.folderEncryptionFailures[folder.ID]; ok {
@@ -1506,7 +1512,13 @@ func (m *model) ccCheckEncryption(fcfg config.FolderConfiguration, folderDevice
 		var err error
 		token, err = readEncryptionToken(fcfg)
 		if err != nil && !fs.IsNotExist(err) {
-			return err
+			if rerr, ok := redactPathError(err); ok {
+				return rerr
+			}
+			return &redactedError{
+				error:    err,
+				redacted: errEncryptionTokenRead,
+			}
 		}
 		if err == nil {
 			m.fmut.Lock()
@@ -1514,7 +1526,14 @@ func (m *model) ccCheckEncryption(fcfg config.FolderConfiguration, folderDevice
 			m.fmut.Unlock()
 		} else {
 			if err := writeEncryptionToken(ccToken, fcfg); err != nil {
-				return err
+				if rerr, ok := redactPathError(err); ok {
+					return rerr
+				} else {
+					return &redactedError{
+						error:    err,
+						redacted: errEncryptionTokenWrite,
+					}
+				}
 			}
 			m.fmut.Lock()
 			m.folderEncryptionPasswordTokens[fcfg.ID] = ccToken
@@ -3258,3 +3277,21 @@ type updatedPendingFolder struct {
 	DeviceID         protocol.DeviceID `json:"deviceID"`
 	ReceiveEncrypted bool              `json:"receiveEncrypted"`
 }
+
+// redactPathError checks if the error is actually a os.PathError, and if yes
+// returns a redactedError with the path removed.
+func redactPathError(err error) (error, bool) {
+	perr, ok := err.(*os.PathError)
+	if !ok {
+		return nil, false
+	}
+	return &redactedError{
+		error:    err,
+		redacted: fmt.Errorf("%v: %w", perr.Op, perr.Err),
+	}, true
+}
+
+type redactedError struct {
+	error
+	redacted error
+}